This invention relates to rotary sprinklers of the type primarily intended for plant irrigation and more particularly, to a governor device for controlling the speed of rotation of such sprinklers.
The speed of rotation of a rotary sprinkler is determined by the forward drive forces tending to rotate the sprinkler, and the inherent retarding forces such as friction and the like which tend to reduce rotational speed. In most rotary sprinklers, for example full circle sprinklers of the reaction drive type, the speed of rotation is usually quite high. With a high speed of rotation, greater friction forces will be developed within the sprinkler and substantial wear of parts within the sprinkler will result. Further, the greater the speed of rotation, the less will become the effective area that the sprinkler will irrigate since water from the sprinkler will tend to spiral and travel less distance from the sprinkler before fall out.
To reduce friction, and therefore increase the effective life of a rotary sprinkler, it is desirable that the speed of rotation be controlled and reduced to relatively low levels. Moreover, by controlling and reducing the speed of rotation, the area irrigated by the sprinkler can be increased.